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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>回调地狱</title>
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<script>
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            sucesscb('11111')
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    ajax('/aaa',(data)=>{
        ajax('/bbb',(data)=>{
            ajax('/ccc',(data)=>{

            },()=>{

            })
        },()=>{

        })
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    })
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